A radio frequency (RF) transmitter may interfere with an RF receiver located nearby, for example, where the transmitter and receiver are co-located on the same platform. The transmitter typically transmits RF energy that includes a main transmit signal surrounded by wideband noise and spurs. The transmitted energy leaks over to the nearby receiver as interference at a relatively high level. The interference includes both high-level narrowband interference (i.e., the main transmit signal) and low-level wideband noise (i.e., the wideband noise and spurs). The interference masks low-level signals of interest in the receiver and may overdrive or even damage sensitive components of the receiver, such as a low noise amplifier in a receiver front-end. Therefore, it is desirable to use of an interference canceler to cancel the interference before the receiver front-end.
Conventional interference canceler techniques and circuits directed to canceling high-level narrowband interference effectively and conventional techniques and circuits directed to canceling low-level wideband interference effectively tend to be different and incompatible because of the disparate characteristics of the two types of interference; a canceling technique that works well for one type of interference does not work well for the other type of interference and vice-versa. As a result, a conventional interference canceler designed to cancel both types of interference disadvantageously includes a large number of circuit components, which drives-up the size, complexity, and cost of the interference canceler.